Thomas C Mehen

Associate Professor

Prof. Thomas Mehen works primarily on Quantum Chromodynamics (QCD) and
the application of effective field theory to problems in hadronic physics.
Effective field theories exploit the symmetries of hadrons to make model
independent predictions when the dynamics of these hadrons are too hard to
solve explicitly. For example, the properties of a hadron containing a
very heavy quark are insensitive to the orientation of the heavy quark
spin. Prof. Mehen has used this heavy quark spin symmetry to make
predictions for the production and decay of heavy mesons and quarkonia at
collider experiments. Another example is the chiral symmetry of QCD which
is a consequence of the lightness of the up and down quarks. The
implications of this symmetry for the force between nucleons is a subject
of Prof. Mehen's research. Prof. Mehen has also worked on effective field
theory for nonrelativistic particles whose short range interactions are
characterized by a large scattering length. This theory has been
successfully applied to low energy two- and three-body nuclear processes.

Some of Prof. Mehen's work is interdisciplinary. For example, techniques
developed for nuclear physics have been used to calculate three-body
corrections to the energy density of a Bose-Einstein condensate whose
atoms have large scattering lengths. Prof. Mehen has also worked on novel
field theories which arise from unusual limits of string theory. Examples
include noncommutative field theories and theories of tachyonic modes on
non-BPS branes.